server.ts

import * as Context from "@effect/data/Context";
import * as Effect from "@effect/io/Effect";
import type { Span } from "@effect/io/Tracer";
import type { RpcResponse } from "@effect/rpc/Resolver";
import type { RpcHandlers, RpcRouter } from "@effect/rpc/Router";
import * as Server from "@effect/rpc/Server";
import * as aws from "aws-lambda";

export const ApiGatewayRequest = Context.Tag<aws.APIGatewayProxyEventV2>();

export interface RpcEventHandler<R extends RpcRouter.Base> {
  (event: aws.APIGatewayProxyEventV2): Effect.Effect<
    Exclude<
      RpcHandlers.Services<R["handlers"]>,
      aws.APIGatewayProxyEventV2 | Span
    >,
    never,
    ReadonlyArray<RpcResponse>
  >;
}

export function make<R extends RpcRouter.Base>(router: R): RpcEventHandler<R> {
  const handler = Server.handler(router);

  return (event) =>
    Effect.provideService(handler(event.body), ApiGatewayRequest, event);
}